Ability to run grcov action for a sub-folder containing Rust sources.

[wdanilo]

Hi! We've been succesfully using grcov for some time now and we have recently refactored our codebase. Our Cargo.toml is no longer located at the top-level. Instead it is inside src/rust folder. When running the CI we got error now: no such file or directory, open '/home/runner/work/ide/ide/Cargo.lock', which is true, as it should point to no such file or directory, open '/home/runner/work/ide/ide/src/rust/Cargo.lock' instead. The problem is that GitHub Actions do not provide a way to set up CWD for third party actions and I haven't found any configuration here how to point grcov to some specific root folder. I'd be very thankful for any help! In case this would be important, this is our repo: https://github.com/luna/ide (branch wip/wd/dev, soon the changes will be on master)

[vcfxb]

I am also wondering about this.

[vcfxb]

Current fix is putting another Cargo.toml in the root directory of the crate, listing it as a workspace and naming the crates within the directory.
ex:

[workspace]
members = ["my-crate"]